Recently purchased a Minn kota edge trolling motor with a 36inch shaft for a plastic boat, what size battery should I get/recommend for this unit? 

The size will depend on how you use it.  I recommend size 27 or larger.  Be sure it is a deep cycle not a cranking battery.  Reserve capacity is the key to how long it will last on a trip.

30 minutes ago, Jig Man said:

The size will depend on how you use it.  I recommend size 27 or larger.  Be sure it is a deep cycle not a cranking battery.  Reserve capacity is the key to how long it will last on a trip.

Any links? I mainly plan to use it for trolling at slow speeds but will crank it up if I need to get out of somewhere 

You can generally never go wrong by getting a larger battery as long as weight or size isn’t an issue. I’d rule out 24s. Group 27s are pretty standard, but you might opt for the next size up, group 29/31s, especially if you are just going with a single battery setup. 

36" bow mount...how far off the water is the TM mounting surface?

If you trailer the boat and charge the battery without removing it get a group 31 size deep cycle marine battery that is located at the stern. Run 6 gage stranded marine wire to the bow. 

You mentioned you plan to troll constantly and occasionally run faster. Is the TM your only pier source?

Tom

1 hour ago, WRB said:

36" bow mount...how far off the water is the TM mounting surface?

If you trailer the boat and charge the battery without removing it get a group 31 size deep cycle marine battery that is located at the stern. Run 6 gage stranded marine wire to the bow. 

You mentioned you plan to troll constantly and occasionally run faster. Is the TM your only pier source?

Tom

no, I bought a bass hunter 120 and they give a mount for bow mount trolling motos, 36 shaft makes sense for smaller boats like that. I also plan on putting a little 2.5hp in the back, I don't even know if i'll get a bow mount, but I want a trolling motor that has more than 55lb maybe a 62lb or something like that. 

1 hour ago, TriStateBassin106 said:

no, I bought a bass hunter 120 and they give a mount for bow mount trolling motos, 36 shaft makes sense for smaller boats like that. I also plan on putting a little 2.5hp in the back, I don't even know if i'll get a bow mount, but I want a trolling motor that has more than 55lb maybe a 62lb or something like that. 

Anything over 55lb trust is going to be 24 volt 2 batteries and twice the weight.

 

Small light weight plastic boat with a gas kicker you can get by with Gr 27 Deep cycle marine battery.

Tom